Lockout device for push button switches having a migratory pivot means



E. F. MEKELBURG 3,182,143 LOCKOUT DEVICE FOR PUSH BUTTON SWITCHES May 4, 1965 HAVING A MIGRATORYIIVOT MEANS 2 Sheets-Sheet 1 Filed Feb. 21, 1962 y 1965 E. F. MEKELBURG 3,182,143

LOCKOUT DEVICE FOR PUSH BUTTON SWITCHES HAVING'YA MIGRATQRY PIVOT MEANS Filed Feb- 21, 1962- 2 Sheets-Sheet 2 H" u uguun m1 Arroelvfx United States Patent 3,182,143 LOCKOUT DEVICE FOR PUSH BUTTON SWITCHES HAVING A MIGRATORY PIVOT MEANS Earl F. Melieiburg, Wauwatosa, Wis, assignor to Squme D Company, Park Ridge, 11]., a corporation of Michigan Filed Feb. 21, 1962, Ser. No. 174,915

6 Claims. (Cl. 200-42) This invention relates to lockout devices for push buttons, and particularly to a lockout device in the form of a frame for locking rubber covered push buttons and push-to-test pilot lights in depressed position.

In push button switches, such as those employing pushto-test pilot lights, and others, the push button or pilot light is generally mounted on a suitable support, such as the cover of a casing or enclosure for a switch, and extends through an opening in the cover so that it is accessible from the exterior of the enclosure.

In many instances, it is desirable that the push button be depressed for certain operations desired, and locked in depressed position so that it cannot be tampered with by unauthorized persons.

The present device relates to a device which may readily be mounted on the cover or wall of an enclosure in association with a push button such that the push button can be depressed readily and locked and held in depressed or retracted position, or can be released for return to an extended position. This device is one in which, while holding the push button in depressed position, can be locked with a suitable padlock or other locking means so that it cannot be tampered with and dislodged so as to free the push button.

The invention is shown as embodied in a suitable frame secured on the cover or wall of the enclosure of a mech anism to be operated by the push button, the frame having a movable part which can be swung to various positions about an axis extending transversely relative to the axis of the push button and, in at least one swung position, can be moved inwardly generally parallel to the axis of the push button so as to engage the outer end thereof and push the push button to a retracted position.

More specifically, an object is to provide a frame, and a carriage thereon which can be swung to the positions described, and which, when in a position in which it holds the push button depressed, can be readily secured in such position by the securing means, thereby securing the push button in retracted position.

Various other objects and advantages will become apparent from the following description wherein reference is made to the drawings, in which:

FIG. 1 is a top plan view of the frame of the present invention, showing it installed on a switch cover which supports a push button, the frame being in position for initiating operation of the push button to depressed position;

FIG. 2 is a front elevation of the structure illustrated in FIG. 1;

7 FIG. 3 is a left end elevation of the structure illustrated in FIGS. 1 and 2;

FIG. 4 is a view similar to FIG. 2 with the carrier in position holding the push button in depressed position;

FIG. 5 is a horizontal sectional view on the line 5-5 in FIG. 2, part thereof being shown in elevation; and

FIG. 6 is a view similar to FIG. 5, showing the carrier holding the push button depressed, and is taken on line 6--6 inVFIG. 4, part thereof being shown in section.

Referring to the drawings, the locking frame is shown in connection with a push button of the type which is enclosed in a suitable resilient sealing cap, such as a push-totest pilot light, its use in connection with other types of push buttons being readily apparent from the illustrated example.

. 3,182,143 Patented May 4, 1965 The push button structure, indicated generally at 1, comprises a suitable threaded body 2 in which a push button 3 is mounted for movement axially endwise, the push button being urged outwardly endwise by suitable spring means within the body 2 to its undepressed, or extended, position. Suitable switch means of the conventional type are provided and may be of the type which is normally closed and opened by depression and release, respectively, of the push button, or normally opened and closed by depression and release, respectively, of the push button, depending upon the particular service in which the push button is to be used. The specific structure of a push button, aside from the fact that it is operated by movement of the button 3 axially inwardly, forms no part of the present invention.

In the form illustrated, the body 2 is provided with an internal shoulder 4 which engages the inner surface of a support, such as an enclosing wall or cover 5 of a switch mechanism. The body 2 has a threaded portion which extends through an opening in the Wall or cover 5 and at the outer face of the cover 5 accommodates a ring nut 7 which clamps the body 2 to the cover 5 with the threaded portion extending to the exterior of the body 2 and beyond the nut 7.

A cap 10, such as disclosed in the copending application of Robert J. Bowman and Earl F. Mekelburg, Serial Number 174,916 filed February 21, 1962, is used to enclose the push button. As therein more fully disclosed, the cap is of flexible or resilient material, such as rubber or translucent plastic. The cap 10 comprises a resilient portion 11 accommodating in its open end an internally disposed ring nut 12 which is bonded to it. The ring nut 12 is arranged for threaded engagement with the body 2 outwardly beyond the nut 7 for mounting the cap 10 in place. The open end of the cap, indicated at 13, is provided with a radially extending peripheral flange 14 adapted for efiecting sealing engagement with the outer surface of the wall or cover 5. Ordinarily, when the nut 12 is screwed firmly against the outer face of the wall or cover 5, it secures the cap 10 with its flange 14 in sealing engagement with the outer face of the cover 5.

In the present instance, however, the nut 12 is used to hold the cap and also to provide a mounting for a lockout device 15.

The lockout device 15 generally comprises a stationary member or yoke 20 having a base 21 and arms 22 spaced apart on opposite ends of the base and extending parallel to each other and generally normal to the plane of the base. The base 21 has an opening 23 which is adapted to accommodate the outer threaded end portion of the body 2, and is provided with a suitable tab or tongue 24 arranged to engage a suitable slot 25' extending endwise of the threaded body portion. A suitable gasket 26 is interposed between the outer face of the cover 5 and the adjacent face of the base 21.

The ring nut 12 of the cap is then screwed into place on the body 2 in the normal fashion, but instead of hearing against the outer face of the cover 5, it bears against the outer face of the base 21, thus holding the base, and thereby the frame, firmly in position, with the arms 22 extending outwardly normal to the surface of the cover 5 and disposed one arm at each side of the pilot cap it).

Mounted on the yoke 25 for movement bodily away from the outer face of the cover 5, generally endwise of the path of movement of the push button, and for rotation about an axis extending transversely of the path, 7

the button to a depressed position. On the other hand, the yoke 39 can be pivoted to a different position in which it is out of alignment with the outer end of the cap and push button whereupon, the push button is accessible and free for operation in the normal manner.

In the form illustrated, the yoke has a base 31 and yoke arms 32. It is mounted on the yoke 29 with its side arms 32 lying alongside the arms 22. The inner ends of the arms 32 are pivotally connected to the arms 22 in order that the base 31 may be swung about the pivotal axis to different positions and moved endwise axially of the push button in some of these positions. For this purpose, migratory pivot means 34 connect the ends of the arms 32 to the ends of the arms 22.

In the form illustrated, migratory pivot means 34 comprise pivots 35 mounted one on each of the arms 32. These pivots are engaged in suitable slots 36, respectively, arranged one slot on each arm 22, and can migrate along the slots toward and away from the base 21 while constrained thereby to positions all of which are parallel to each other.

The slots are parallel to each other and of like con figuration. Each slot 36 has its inner end at the base 21 and extends generally outwardly from the base 21 toward the outer end of its arm 22, the inner end portion of each slot being substantially at said plane and an intermediate portion, outwardly from the inner end portion, sloping away from said plane from its inner end toward its outer end. Each slot 36 has an outer end portion 38 which slopes at a more abrupt angle away from the plane than does the intermediate portions in a direction outwardly from the base. Thus each slot slopes in a direction away from the axis of the push button. This outer end portion 38 of each slot is adequate to receive an associated one of the pivots 35 and permit pivoting of the yoke 30 about the axis of the pivots. Likewise, it permits the pivot 35 to travel along the slot toward the base 21. Near the inner ends of the slots the arms have notches 39 which open into the slots. Each notch 39 is disposed at the same side of said plane through the axis of the push button and parallel to the pivotal axis as is the outer end portion 33 of the slot. The notch 39 opens generally toward the base 21 whereby the pivots 35 may be dropped into their associated notches 39, and while therein, cannot be removed by pulling the locking member 36 outwardly. Instead, the pivots can be displaced from the notches 39 only by pushing the pivots upwardly toward the opposite sides of the slots 36 and clear of the notches 39.

The locking member 36 carries on its base 31 a depress ing element 4%} which is so positioned that when the locking member 30 is positioned with its pivotal means in the notches 39 and the frame swung about the pivotal axis to locking position, the element 40 is in engagement with the outer end of the cap and thereby with the outer end of the depressed push button. The arms 22 and the arms 32 are provided with apertures 42 and 43, respectively. These apertures are positioned so that, when the pivot means 34 are in the notches 33 and the element 40 is aligned with the axis of the push button and is holding it in depressed condition, the apertures are in alignment with each other, thus providing suitable registering means by which the locking member can be locked in proper position. For example, the aligned apertures 42 and 43 may receive the hasp portion of a suitable padlock, or a headed rod, having an aperture at the end opposite the head, may be passed through the apertures and a padlock hasp passed through the aperture.

The outer end portions of the slots 36'slope relative to the axis of the push button at such an angle that when the pivots 35 are in the outermost ends of the slots and pressure is applied to the base 31 at the margin nearest the axis of the push button, the pivots 35 will slide along the slots 36 toward the base 31, and the member 30 will swing about the pivotal axis concurrently in a clockwise direction. This movement will continue until the pivots 35 enter the notches 39, whereupon the push button will be depressed by the member 40 and the apertures 42 and 43 will be aligned for reception of the padlock.

On the other hand, with the yoke 20 in the locking position, pressure applied at the opposite margin of the base 31, which is the one farthest from the axis of the push button, will cause the pivots 35 to move upwardly out of the notches 39 and, concurrently, will cause the yoke 30 to swing counterclockwise about the pivotal axis. This action moves the pivots 35 out of the notches 39. Thereupon the self-restoring force of the cap 10, or the force of the return spring embodied in the push button structure and urging the button outwardly from depressed position, will cause the yoke 30 to move outwardly away from the base 21. Since the pivots 35 are freed from the notches 39, they slide to the outer ends of the slots 36, the yoke member 30 meanwhile swinging counterclockwise out of alignment with the push button.

It is apparent, therefore, that, with this arrangement, a very simple and effective means is provided for locking push buttons in the depressed position, and for releasing them, selectively.

The structure is one which can be made economically and which can be installed in place readily by the means which normally hold the push button itself in installed condition in the switch cover.

Having thus described my invention, I claim:

1. A lockout device for a push button, and comprising a stationary member having a base portion adapted to be connected to a support, a movable lockout member, migratory pivot means connecting the members together for rotation about the axis of the pivot means in different migrant positions of the pivot means, means supporting the pivot means for bodily migratory movement transversely of the pivotal axis to migrant positions wherein the migrant axes of rotation of the members are parallel to each other, and means for constraining the migratory movement of the pivot means to movement generally. toward and away from said portion of the stationary member, additional means on the stationary member engageable with the pivot means when the pivot means is moved toward said portion to one migrant position and operative when engaged, to constrain the pivot means from movement away from said portion while permitting free relative rotation of the members about the axis of the pivot means in said one migrant position, and cooperable means on the members adapted to be secured in fixed position relative to each other when the pivot means is in said one migrant position and the members, while in said one migrant position, are in a predetermined relatively rotated position.

2. A lockout device and push button combination, comprising a support, a push button carried thereby and extending outwardly from one face thereof and movable in a path toward and away therefrom, a stationary member carried by the support at said face, a lockout member, migrant pivot means extending generally transversely of the path of the push button and connecting the lockout member to the stationary member for bodily migrant movement of the lookout member relative to the stationary member, transversely of the axis of the pivot means, toward and away from the support generally endwise of the path of movement of the push button and for rotation, in migrant positions to which the lockout member has been moved bodily, about axes extending generally transversely of said path, button depressing means on the lookout member and positioned to engage and depress the push button upon said bodily movement of the lockout member toward the support to a predetermined migrant operative position and rotation of the lockout member into a final rotated operative position of the lockout member about its rotational axis while the lookout member is in said predetermined migrant position, complementary registerable means on the members and positioned for registry when the lookout member is in both of said operative positions, concurrently, and adapted, when registered, for cooperation with locking means for locking the members in said operative positions, and said button depressing means being movable to releasing relation with respect to the push button upon migrant bodily movement of the lockout member away from the support out of said predetermined migrant operative position to another migrant position and rotation of the lookout member about said pivot means out of said rotated operative position while the lookout member is in said other migrant position so that the lookout member is out of both of said operative positions concurrently.

3. The structure according to claim 2 wherein said support comp-rises a first yoke having a first base adapted for connection to the support and a first pair of laterally spaced supporting arms on the base and extending out- Wardly from the support at opposite sides of the path or" the push button, said locking member comprises a second yoke having a second base and a second pair of arms extending therefrom and disposed in face to face relation to the first arms, respectively, pivot means connecting the arms of one pair to those of the other pair, the arms of one pair having aligned slots accommodating the pivot means and supporting them for bodily movement along the slots and for aifording relative rotational movement of the yokes about the axis of the pivot means, and each of said slots being elongated and extending endwise in a direction generally toward and away from the base supporting the arms of said one pair.

4. The structure according to claim 3 wherein the slots are in the first pair of arms.

5. The structure according to claim 4 wherein the said slots extend bias to a plane which is through the pivotal axis and is parallel to the axis of the push button, and

said first arms having notches near the first base and open generally toward the first base and communicating with the slots, respectively, for receiving the pivot means by movement of the pivot means transversely of their axis While positioned at the notches, said notches having wall portions positioned for engaging the pivot means and preventing bodily movement of the pivot means away from the first base while the pivot means are in the notches, said registerable means being movable into registration while the pivot means are in the notches, and being oifset transversely of the slots from the notches so that, when the registerable means are locked in registration, the yokes cannot be rotated about the axis of the pivot means and the pivot means cannotbe disengaged fronrsaid notches, whereby the button depressing means are locked in position for holding the push'button in depressed position.

6. The structure according to claim 2 wherein the statie-nary member has a base with one face facing the support, and with a passage therein, the push button has a threaded body portion extending through the passage, a protective flexible cap covers the push button and has an internally threaded ring nut adjacent its open end in threaded engagement with the body portion, the open end of said cap being juxtaposed against the other face of the base and clamping it to the support.

References liter by the Examiner UNITED STATES PATENTS 1,45 0,046 3/ 23 Newton 20042 1,473,386 11/23 Scott ZOO-42 2,447,226 8/48 Bennett 200-42 2,659,780 11/53 Berger 2O042 BERNARD A. GILHEANY, Primary Examiner. 

1. A LOCKOUT DEVICE FOR A PUSH BUTTON, AND COMPRISING A STATIONARY MEMBER HAVING A BASE PORTION ADAPTED TO BE CONNECTED TO A SUPPORT, A MOVABLE LOCKOUT MEMBER, MIGRATORY PIVOT MEANS CONNECTING THE MEMBERS TOGETHER FOR ROTATION ABOUT THE AXIS OF THE PIVOT MEANS IN DIFFERENT MIGRANT POSITIONS OF THE PIVOT MEANS, MEANS SUPPORTING THE PIVOT MEANS FOR BODILY MIGRATORY MOVEMENT TRANSVERSELY OF THE PIVOTAL AXIS OF MIGRANT POSITIONS WHEREIN THE MIGRANT AXES OF ROTATION OF THE MEMBERS ARE PARALLEL TO EACH OTHER, AND MEANS FOR CONSTRAINING THE MIGRATORY MOVEMENT OF THE PIVOT MEANS TO MOVEMENT GENERALLY TOWARD AND AWAY FROM SAID PORTION OF THE STATIONARY MEMBER, ADDITIONALLY MEANS ON THE STATIONARY MEMBER ENGAGEABLE WITH THE PIVOT MEANS WHEN THE PIVOT MEANS IS MOVED TOWARD SAID PORTION TO ONE MIGRANT POSITION AND OPERATIVE WHEN ENGAGED, TO CONNSTRAIN THE PIVOT MEANS FOR MOVEMENT AWAY FROM SAID PORTTION WHILE PERMITTING FREE RELATIVE ROTATION OF THE MEMBERS ABOUT THE AXIS OF THE PIVOT MEANS IN SAID ONE MIGRANT POSITION, AND COOPERABLE MEANS ON THE MEMBERS ADAPTED TO BE SECURED IN FIXED POSITION RELATIVE TO EACH OTHER WHEN THE PIVOT MEANS IS IN SAID ONE MIGRANT POSITION AND THE MEMBERS, WHILE IN SAID ONE MIGRANT POSITION, ARE IN A PREDETERMINED RELATIVELY ROTATED POSITION. 